Scientists Thrilled to See Layers in Mars Rocks Near Opportunity
January 27, 2004
New pictures from NASA's Mars Exploration Rover Opportunity reveal
thin layers in rocks just a stone's throw from the lander platform
where the rover temporarily sits.
Geologists said that the layers -- some no thicker than a finger --
indicate the rocks likely originated either from sediments carried
by water or wind, or from falling volcanic ash. "We should be able
to distinguish between those two hypotheses," said Dr. Andrew Knoll
of Harvard University, Cambridge, a member of the science team for
Opportunity and its twin, Spirit. If the rocks are sedimentary,
water is a more likely source than wind, he said.
The prime goal for both rovers is to explore their landing areas for
clues in the rocks and soil about whether those areas ever had
watery environments that could possibly have sustained life.
Controllers at NASA's Jet Propulsion Laboratory, Pasadena, Calif.,
plan to tell Opportunity tonight to start standing up from the
crouched and folded posture in which it traveled to Mars.
"We're going to lift the entire rover, then the front wheels will be
turned out," said Mission Manager Jim Erickson of JPL. Several more
days of activities are still ahead before the rover will be ready to
drive off the lander.
"We're about to embark on what could be the coolest geological field
trip in history," said Dr. Steve Sqyures of Cornell University,
Ithaca, N.Y., principal investigator for the rovers' science
payload.
The layered rocks are in a bedrock outcrop about 30 to 45
centimeters (12 to 18 inches) tall, and only about eight meters (26
feet) away from where Opportunity came to rest after bouncing to a
landing three days ago. Examination of their texture and
composition with the cameras and spectrometers on the rover may soon
reveal whether they are sedimentary, Knoll predicted.
Scientists also hope to determine the relationship between those
light-colored rocks and the dark soil that covers most of the
surrounding terrain. The soil may contain the mineral hematite,
which was identified from orbit and motivated the choice of
Opportunity's landing area, Squyres said.
Opportunity successfully used its high-gain antenna for the first
time yesterday. The rover is losing some if its battery charge each
night, apparently due to an electric heater at the shoulder joint of
the rover's robotic arm. A thermostat turns on the heater whenever
the air temperature falls to levels that Opportunity is experiencing
every night. The heater is not really needed when the arm is not in
use, but ground control has not been able to activate a switch
designed to override the thermostat, Erickson said. Mission
engineers are working to confirm the diagnosis, determine the
ramifications of the power drain, and propose workarounds or fixes.
Meanwhile, engineers working on Spirit have determined that the high-
gain antenna on that rover is likely in working order despite
earlier indications of a possible problem. They are continuing to
take information out of Spirit's flash memory. Results from a
testbed simulator of the rover's electronics supported the diagnosis
of a problem with management of the flash memory, reported JPL's
Jennifer Trosper, mission manager.
JPL, a division of the California Institute of Technology in
Pasadena, manages the Mars Exploration Rover project for NASA's
Office of Space Science, Washington, D.C. Images and additional
information about the project are available from JPL at
http://marsrovers.jpl.nasa.gov and from Cornell University at
http://athena.cornell.edu.
